package com.xuecheng.content.service.impl;

import com.alibaba.fastjson.JSON;
import com.xuecheng.base.exception.CommonError;
import com.xuecheng.base.exception.XueChengPlusException;
import com.xuecheng.content.config.MultipartSupportConfig;
import com.xuecheng.content.feignclient.MediaServiceClient;
import com.xuecheng.content.mapper.CourseBaseMapper;
import com.xuecheng.content.mapper.CourseMarketMapper;
import com.xuecheng.content.mapper.CoursePublishMapper;
import com.xuecheng.content.mapper.CoursePublishPreMapper;
import com.xuecheng.content.model.dto.CourseBaseInfoDto;
import com.xuecheng.content.model.dto.CoursePreviewDto;
import com.xuecheng.content.model.dto.TeachPlanDto;
import com.xuecheng.content.model.po.CourseBase;
import com.xuecheng.content.model.po.CourseMarket;
import com.xuecheng.content.model.po.CoursePublish;
import com.xuecheng.content.model.po.CoursePublishPre;
import com.xuecheng.content.service.CourseBaseInfoService;
import com.xuecheng.content.service.CoursePublishService;
import com.xuecheng.content.service.TeachPlanService;
import com.xuecheng.messagesdk.model.po.MqMessage;
import com.xuecheng.messagesdk.service.MqMessageService;
import com.xuecheng.messagesdk.service.impl.MqMessageServiceImpl;
import freemarker.template.Configuration;
import freemarker.template.Template;
import lombok.extern.slf4j.Slf4j;
import org.apache.commons.io.IOUtils;
import org.redisson.api.RLock;
import org.redisson.api.RedissonClient;
import org.springframework.beans.BeanUtils;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.data.redis.core.RedisTemplate;
import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Transactional;
import org.springframework.ui.freemarker.FreeMarkerTemplateUtils;
import org.springframework.util.StringUtils;
import org.springframework.web.multipart.MultipartFile;

import javax.annotation.Resource;
import java.io.File;
import java.io.FileOutputStream;
import java.io.InputStream;
import java.nio.charset.StandardCharsets;
import java.time.LocalDateTime;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.Random;
import java.util.concurrent.TimeUnit;

/**
 * Created with IntelliJ IDEA.
 * Description:
 * User: ws
 * Date: 2024-07-06
 * Time: 22:01
 */

@Slf4j
@Service
public class CoursePublishServiceImpl implements CoursePublishService {

    @Resource
    CourseBaseInfoService courseBaseInfoService;

    @Resource
    TeachPlanService teachplanService;

    @Resource
    CourseBaseMapper courseBaseMapper;

    @Resource
    CourseMarketMapper courseMarketMapper;

    @Resource
    CoursePublishPreMapper coursePublishPreMapper;

    @Resource
    CoursePublishMapper coursePublishMapper;

    @Resource
    MqMessageService mqMessageService;

    @Resource
    MediaServiceClient mediaServiceClient;

    @Resource
    RedisTemplate redisTemplate;

    @Resource
    RedissonClient redissonClient;


    @Override
    public CoursePreviewDto getCoursePreviewInfo(Long courseId) {

        //课程基本信息、营销信息
        CourseBaseInfoDto courseBaseInfo = courseBaseInfoService.getCourseBaseInfo(courseId);

        //课程计划信息
        List<TeachPlanDto> teachplanTree = teachplanService.findTeachPlanTree(courseId);

        CoursePreviewDto coursePreviewDto = new CoursePreviewDto();
        coursePreviewDto.setCourseBase(courseBaseInfo);
        coursePreviewDto.setTeachplans(teachplanTree);
        return coursePreviewDto;
    }


    @Transactional
    @Override
    public void commitAudit(Long companyId, Long courseId) {

        //约束校验
        CourseBase courseBase = courseBaseMapper.selectById(courseId);
        if (courseBase == null) {
            XueChengPlusException.cast("课程不存在");
        }
        //课程审核状态
        String auditStatus = courseBase.getAuditStatus();
        //当前审核状态为已提交不允许再次提交
        if ("202003".equals(auditStatus)) {
            XueChengPlusException.cast("当前为等待审核状态，审核完成可以再次提交。");
        }
        //本机构只允许提交本机构的课程
        if (!courseBase.getCompanyId().equals(companyId)) {
            XueChengPlusException.cast("不允许提交其它机构的课程。");
        }

        //课程图片是否填写
        if (StringUtils.isEmpty(courseBase.getPic())) {
            XueChengPlusException.cast("提交失败，请上传课程图片");
        }

        //添加课程预发布记录
        CoursePublishPre coursePublishPre = new CoursePublishPre();
        //课程基本信息加部分营销信息
        CourseBaseInfoDto courseBaseInfo = courseBaseInfoService.getCourseBaseInfo(courseId);
        BeanUtils.copyProperties(courseBaseInfo, coursePublishPre);
        //课程营销信息
        CourseMarket courseMarket = courseMarketMapper.selectById(courseId);
        //转为json
        String courseMarketJson = JSON.toJSONString(courseMarket);
        //将课程营销信息json数据放入课程预发布表
        coursePublishPre.setMarket(courseMarketJson);

        //查询课程计划信息
        List<TeachPlanDto> teachplanTree = teachplanService.findTeachPlanTree(courseId);
        if (teachplanTree == null || teachplanTree.isEmpty()) {
            XueChengPlusException.cast("提交失败，还没有添加课程计划");
        }
        //转json
        String teachplanTreeString = JSON.toJSONString(teachplanTree);
        coursePublishPre.setTeachplan(teachplanTreeString);

        //设置预发布记录状态,已提交
        coursePublishPre.setStatus("202003");
        //教学机构id
        coursePublishPre.setCompanyId(companyId);
        //提交时间
        coursePublishPre.setCreateDate(LocalDateTime.now());
        CoursePublishPre coursePublishPreUpdate = coursePublishPreMapper.selectById(courseId);
        if (coursePublishPreUpdate == null) {
            //添加课程预发布记录
            coursePublishPreMapper.insert(coursePublishPre);
        } else {
            coursePublishPreMapper.updateById(coursePublishPre);
        }

        //更新课程基本表的审核状态
        courseBase.setAuditStatus("202003");
        courseBaseMapper.updateById(courseBase);
    }


    /**
     * @param courseId 课程id
     * @return void
     * @description 保存消息表记录
     */
    private void saveCoursePublishMessage(Long courseId) {
        MqMessage mqMessage = mqMessageService.addMessage("course_publish", String.valueOf(courseId), null, null);
        if (mqMessage == null) {
            XueChengPlusException.cast(CommonError.UNKNOWN_ERROR);
        }
    }

    @Transactional
    @Override
    public void publish(Long companyId, Long courseId) {

        // 查询课程预发布表
        //约束校验
        //查询课程预发布表
        CoursePublishPre coursePublishPre = coursePublishPreMapper.selectById(courseId);
        if (coursePublishPre == null) {
            XueChengPlusException.cast("请先提交课程审核，审核通过才可以发布");
        }
        //本机构只允许提交本机构的课程
        if (!coursePublishPre.getCompanyId().equals(companyId)) {
            XueChengPlusException.cast("不允许提交其它机构的课程。");
        }
        //课程审核状态
        String auditStatus = coursePublishPre.getStatus();
        //审核通过方可发布
        if (!"202004".equals(auditStatus)) {
            XueChengPlusException.cast("操作失败，课程审核通过方可发布。");
        }
        // 向课程发布表写入
        CoursePublish coursePublish = new CoursePublish();
        BeanUtils.copyProperties(coursePublishPre, coursePublish);
        CoursePublish coursePublishObj = coursePublishMapper.selectById(courseId);
        if (coursePublishObj == null) {
            coursePublishMapper.insert(coursePublish);
        } else {
            coursePublishMapper.updateById(coursePublish);
        }
        // 向消息表写入
        saveCoursePublishMessage(courseId);
        // 将课程预发布表删除
        coursePublishPreMapper.deleteById(courseId);


    }


    @Override
    public File generateCourseHtml(Long courseId) {

        //静态化文件
        File htmlFile = null;

        try {
            //配置freemarker
            Configuration configuration = new Configuration(Configuration.getVersion());

            //加载模板
            //选指定模板路径,classpath下templates下
            //得到classpath路径
            String classpath = this.getClass().getResource("/").getPath();
            String path = java.net.URLDecoder.decode(classpath, StandardCharsets.UTF_8.name());
            configuration.setDirectoryForTemplateLoading(new File(path + "templates/"));
            //设置字符编码
            configuration.setDefaultEncoding("utf-8");

            //指定模板文件名称
            Template template = configuration.getTemplate("course_template.ftl");

            //准备数据
            CoursePreviewDto coursePreviewInfo = this.getCoursePreviewInfo(courseId);

            Map<String, Object> map = new HashMap<>();
            map.put("model", coursePreviewInfo);

            //静态化
            //参数1：模板，参数2：数据模型
            String content = FreeMarkerTemplateUtils.processTemplateIntoString(template, map);
//            System.out.println(content);
            //将静态化内容输出到文件中
            InputStream inputStream = IOUtils.toInputStream(content);
            //创建静态化文件
            htmlFile = File.createTempFile("course", ".html");
            log.debug("课程静态化，生成静态文件:{}", htmlFile.getAbsolutePath());
            //输出流
            FileOutputStream outputStream = new FileOutputStream(htmlFile);
            IOUtils.copy(inputStream, outputStream);
        } catch (Exception e) {
            log.error("课程静态化异常:{}", e.toString());
            XueChengPlusException.cast("课程静态化异常");
        }

        return htmlFile;
    }

    @Override
    public void uploadCourseHtml(Long courseId, File file) {
        MultipartFile multipartFile = MultipartSupportConfig.getMultipartFile(file);
        String course = mediaServiceClient.upload(multipartFile, "course/" + courseId + ".html");
        if (course == null) {
            XueChengPlusException.cast("上传静态文件异常");
        }
    }

    @Override
    public CoursePublish getCoursePublish(Long courseId) {
        return coursePublishMapper.selectById(courseId);
    }


//    public CoursePublish getCoursePublishCache(Long courseId) {
//
//        //查询缓存
//        Object jsonObj = redisTemplate.opsForValue().get("course:" + courseId);
//        if (jsonObj != null) {
//            String jsonString = jsonObj.toString();
//            CoursePublish coursePublish = JSON.parseObject(jsonString, CoursePublish.class);
//            return coursePublish;
//        } else {
//            synchronized (this) {
//                jsonObj = redisTemplate.opsForValue().get("course:" + courseId);
//                if (jsonObj != null) {
//                    String jsonString = jsonObj.toString();
//                    CoursePublish coursePublish = JSON.parseObject(jsonString, CoursePublish.class);
//                    return coursePublish;
//                }
//                System.out.println("=========从数据库查询==========");
//                //从数据库查询
//                CoursePublish coursePublish = getCoursePublish(courseId);
//                //设置过期时间300秒
//                redisTemplate.opsForValue().set("course:" + courseId, JSON.toJSONString(coursePublish), 300, TimeUnit.SECONDS);
//                return coursePublish;
//            }
//        }
//    }


    public CoursePublish getCoursePublishCache(Long courseId) {

        //查询缓存
        Object jsonObj = redisTemplate.opsForValue().get("course:" + courseId);
        if (jsonObj != null) {
            String jsonString = jsonObj.toString();
            CoursePublish coursePublish = JSON.parseObject(jsonString, CoursePublish.class);
            return coursePublish;
        } else {
            // 使用 redisson 获取锁，解决 setnx 的缺陷（自动监控锁的状态，续杯，解锁）
            RLock lock = redissonClient.getLock("coursequerylock:" + courseId);
            lock.lock();
            try {
                jsonObj = redisTemplate.opsForValue().get("course:" + courseId);
                if (jsonObj != null) {
                    String jsonString = jsonObj.toString();
                    CoursePublish coursePublish = JSON.parseObject(jsonString, CoursePublish.class);
                    return coursePublish;
                }
                System.out.println("=========从数据库查询==========");
                //从数据库查询
                CoursePublish coursePublish = getCoursePublish(courseId);
                //设置过期时间300秒
                redisTemplate.opsForValue().set("course:" + courseId, JSON.toJSONString(coursePublish), 300, TimeUnit.SECONDS);
                return coursePublish;
            } finally {
                // 手动释放锁
                lock.unlock();
            }

        }
    }
}

